Ok here is the scenario, I recently put a 1966 383 and 727 out of a new yorker, into my 1970 dodge truck. Now the back-up lights are on in drive, as I am aware of the older transmission having the different Neutral Safety Switch and Rooster comb to activate that switch. I am wondering if the valve body out of my small block 727 that was in the truck, can be put into the 66 transmission, and therefore able to use the Rooster comb and 3 prong switch? I have included a picture of the 3 different types of switches and the comb, the middle being the 66 type, and the one on the right being the 69 and up type that I need. Any help apreciated. thanks!

You could either switch in the valve body or swap the rooster comb .

I am using a 71 valve body in my 67 trans and the 3 prong plug, works fine. My understanding on changing the rooster comb is that a 69 only will work on the early transmissions. 70 up does not work, correct me if I am wrong.

'69 and '70 (on the left in the pic below) will work in a '66, '71 and later won't unless the valve cover plate is also changed.

Thank you for the replies so far, its been very helpful. So can I just change the rooster tail or do I need to swap the whole valve body to do so? I'm not sure...

Ok, Thank you very much for the info!

Does anyone have these for sale? I can't seem to find any...thanks!

Put a WANTED AD in the classified section HERE